It is possible, on a computer with 2 hard drives, to use and update the same blockchain using Bitcoin Core?
The first HDD is a dual boot Windows 10 / Linux, and the second is only used for Bitcoin Core and the blockchain.
Windows and Linux are using two different files systems but you can read and access everything unless you are using some data encryption, and you can even hide or remove specific hard drive in partition manager software.
Encrypted data is much better than having regular data but it can slow down reading times a lot.